Hack a Day reader [Stephan Martin] has assembled a clever bargain-basement system using an Arduino-driven stepper motor and a reduction gear system built up from LEGO Technic parts, along with ...

This solar tracker system uses the Arduino UNO board, a servomotor, 2 LDRs and 2 resistors to rotate the solar panel towards the Sun or a source of light. Here https ...

but we do know her Arduino does. Her build uses the ubiquitous HC-SR04 SONAR sensor and a servo. This is a great use for a servo since a standard servo motor without modifications only moves ...